Gerrymander: It’s a dirty word. Everyone knows it’s a political insult, but not everyone understands exactly what it means. And even many of those who know what gerrymandering is don’t fully grasp how it completely dominates American politics.

Welcome to Gerrymandering 101.

Pundits across the political spectrum are now noting that the 2010 Republican tsunami was bigger and more significant than it might appear on the surface, because the Republicans not only won a record number of federal races, they also utterly crushed the Democrats in local races, winning at least 675 seats in state legislatures. This spells doom for the Democrats because next year the states will re-draw the congressional district lines to accommodate the results of the 2010 census:

When the 2010 Census results are announced next month, the 435 House seats will be reapportioned to the states, and state officials will draw new district lines in each state. … Republicans look to have a bigger advantage in this redistricting cycle they’ve ever had before.

“Advantage”? Advantage in what? Isn’t drawing little squiggly lines on a map the most boring and least consequential job imaginable?

Think again. Remember this motto: He Who Draws The Lines Determines The Winners.

Yes, it’s that simple. If you can’t quite visualize how gerrymandering can possibly succeed — after all, the number of voters stays the same no matter how you group them, and if you exclude opposition voters from one district, you necessarily must include them in an adjacent district — keep reading. This essay explains in no uncertain terms how manipulating district boundaries can lead to a complete subversion of true representative government.